Imodium's overdose potential underscores need for regulation

Some opioid addicts are now turning to the anti-diarrhea medication loperamide.

Some opioid addicts are now turning to the anti-diarrhea medication loperamide. (Image Source/Getty Images/Image Source)

Mena Gaballah, H. Neal Reynolds , Thomas Scalea

When people with substance abuse disorders can’t secure their usual drug — either because it’s too expensive, scarce or dangerous to obtain — they’ll often turn to over-the-counter substitutes to achieve some kind of high. That’s how cough syrup containing dextromethorphan became known as the “poor man’s PCP.” And it’s how the common anti-diarrheal Imodium, the trade name for loperamide, earned the label “poor man’s methadone.”

Loperamide typically remains in the bowel, but in extremely high quantities, it is absorbed into the blood stream and acts on the same receptors in the brain as heroin, causing euphoria.

Increasingly, emergency departments are admitting patients for loperamide overdose. The drug can be purchased from Costco, Walmart or Amazon in extraordinary quantities — cheaply and without a prescription. Recently, we admitted a patient with a history of opioid abuse who was found unresponsive with a highly lethal heart rhythm. Family members informed us that the patient had purchased thousands of loperamide caplets online, and testing confirmed toxic blood levels. The highest level of life support available anywhere in the world ultimately led to that patient’s survival, but what about the next patient?

In Baltimore, Mayor Catherine Pugh has put the opioid epidemic at the center of her “Keeping Baltimore Healthy” strategy. Her plan includes expanded access to evidence-based drug treatment to improve public health and safety. She has pledged to work with developers to build and expand facilities that treat the underlying problems causing addiction, which may include increasing methadone clinic access, needle-exchange programs, church-based or secular counseling and partnerships with major health-systems. These are all commendable actions, but we cannot forget that over the counter (OTC) substances can also be a threat to public health, in addition to prescription opioids and street drugs like heroin.

In recent years, legislation has limited the sale of OTC drugs with high abuse potential such as pseudoephedrine and dextromethorphan. Specifically, pharmacies are restricted from selling more than 3.6 grams of pseudoephedrine per day or 9 grams per month and must keep records of purchases. In an increasing number of states, dextromethorphan sale to minors is also restricted. Tighter regulation for loperamide, like dextromethorphan and pseudoephedrine, could be developed either at state or federal levels.

In 1976, the Food and Drug Administration approved loperamide as a controlled substance requiring a prescription. Twelve years later, however, loperamide was downgraded to an OTC medication. One solution would be to encourage federal regulators to reverse their decision on loperamide and return it to controlled status. In so doing, providers could collect data on its use and manage the risks of its abuse through Maryland’s Prescription Drug Monitoring program. This is unlikely to happen, however. Thus far, the FDA has only said it is willing to work with loperamide manufacturers to make it more difficult to access a high number of doses quickly, but limiting the number per package or using blister packaging.

The effects of this OTC drug are under-appreciated. Thus, even well-trained physicians may not consider loperamide as the cause when patients present with symptoms resembling opioid toxicity with major cardiac rhythmic problems. And even if they do, there may not be much they can do about it. The degree of life support used for our patient is only available at a small number of hospitals, and it is not a solution.

Families must be vigilant and recognize that large quantities of loperamide, or any drug in the house, is not normal. Just as the effects of pseudoephedrine and dextromethorphan were publicized and became understood, the medical community, politicians, and legislators must now set their sights on availability, use and toxicity of loperamide. Furthermore, the imaginative community of drug seekers will find yet other alternatives: We must be ever vigilant. Failure to do so will mean many more patients overdosing with additional preventable deaths.

Mena Gaballah (mena.gaballah@umaryland.edu) is a dual-degree student at the University of Maryland School of Pharmacy and the University of Maryland School of Law. Dr. H. Neal Reynolds (hneal.reynolds@gmail.com) is an associate professor of medicine at the University of Maryland School of Medicine and co-director of the Multi-Trauma Intensive Care Unit at the R Adams Cowley Shock Trauma Center, where Dr. Thomas Scalea is physician-in-chief. Dr. Scalea (tscalea@umm.edu) is also director of the Program in Trauma at the University of Maryland School of Medicine.